JP4323259B2 - Electrolyte analyzer - Google Patents

Description

  The present invention relates to an electrolyte analyzer, and more particularly to an electrolyte analyzer that measures an electrolyte concentration in a sample such as urine or serum.

  Conventionally, for example, an electrolyte analyzer for measuring an electrolyte concentration (ion concentration) in a sample such as urine or serum using an ion selective electrode, that is, measurement using an ion selective electrode (hereinafter referred to as “ISE (Ion Selective Electrolyte analyzers employing the principle of “Electrodes” (also known as “measurement”) are known.

  Such an electrolyte analyzer uses an ion-selective electrode and a reference electrode, and the electromotive force (the potential of the ion-selective electrode and the potential of the reference electrode is generated by diluting the sample with a diluent. In addition to measuring the potential difference), the electromotive force of the standard solution is measured, and the electrolyte concentration of the component to be measured contained in the sample solution is measured from the measurement data of each of the sample solution and the standard solution (for example, patent document) 1).

In the electrolyte analyzer, the potential at the ion selective electrode is represented by the following formula.
E = E ₀ + (RT / nF) lna
Where E is the potential of the ion selective electrode, E ₀ is the standard electrode potential, n is the ionic valence involved in the reaction, F is the Faraday constant, R is the gas constant, T is the absolute temperature, and a is the ion activity. is there.

Japanese Patent Laid-Open No. 8-17885

  However, in the measurement of the electrolyte concentration in the electrolyte analyzer, the absolute temperature (T) is included as a factor, as is apparent from the above formula. Therefore, if there is a temperature difference between the sample solution and the standard solution, the temperature difference between the sample solution electromotive force measured using the ion selective electrode and the reference electrode and the standard solution electromotive force There is a problem that the size is superposed and a larger difference than necessary is generated, and the electrolyte concentration of the component to be measured contained in the sample solution cannot be accurately measured. To further describe this problem, there are multiple sample solutions generated from the same sample, there is no temperature difference between one sample solution and the standard solution, and there is a temperature difference between the other sample solution and the standard solution. If there is, the electrolyte concentration of the component to be measured contained in one sample solution obtained as a measurement result is completely different from the electrolyte concentration of the component to be measured contained in the other sample solution. End up.

  Therefore, in order to cope with such a problem, in the conventional electrolyte analyzer, the temperature of the sample solution and the standard solution is constant, the temperature of the sample solution and the standard solution is detected by, for example, a thermistor, and the like. A device equipped with a device for performing temperature correction from the detected temperature has been proposed.

  However, providing such a device for constant temperature and a device for performing temperature correction not only leads to an increase in the size of the entire electrolyte analyzer, but also the electrolyte concentration of the component to be measured contained in the sample solution. This is not preferable because it complicates the measurement.

  In view of the above circumstances, an object of the present invention is to provide an electrolyte analyzer that can accurately and easily measure the electrolyte concentration of a component to be measured contained in a sample solution without increasing the size of the entire apparatus. And

  In order to achieve the above object, an electrolyte analyzer according to claim 1 of the present invention comprises a diluent supply means for supplying a diluent for diluting a sample to produce a sample solution, and a standard solution. By measuring the electromotive force of each of the sample solution and the standard solution using a standard solution supply means for supplying the dilution solution to the dilution container and an ion-selective electrode. A heat exchanging means for exchanging heat between the diluent supplied by the diluent supply means and the standard solution supplied by the standard solution supply means in an electrolyte analyzer comprising a measuring means for measuring the concentration It is provided with.

  The electrolyte analyzer according to claim 2 of the present invention is the electrolyte analyzer according to claim 1, wherein the dilution liquid supply by the dilution liquid supply means and the standard liquid supply by the standard liquid supply means are alternately performed. It is characterized by being.

  According to the first aspect of the present invention, the heat exchanging means exchanges heat between the diluent supplied by the diluent supplying means and the standard liquid supplied by the standard liquid supplying means. The temperatures of the liquid and the standard liquid are almost equal, and the temperature difference between the two can be made extremely close to zero. Thereby, the temperature difference between the sample solution and the standard solution measured by the measuring means is less likely to occur, and the measured electromotive force is not affected by the temperature difference between the sample solution and the standard solution. Therefore, it is possible to accurately and easily measure the electrolyte concentration of the component to be measured contained in the sample solution without increasing the size of the entire apparatus.

  According to invention of Claim 2 of this invention, in addition to the effect which the invention of said Claim 1 show | plays, there can exist the following effects. Since the supply of the diluting solution by the diluting solution supply means and the supply of the standard solution by the standard solution supplying means are alternately performed, the standard solution also serves as the washing of the dilution container and the measuring means. Therefore, there is no need to provide time for cleaning, and the measurement time can be shortened.

  Exemplary embodiments of an electrolyte analyzer according to the present invention will be described below in detail with reference to the accompanying drawings. In addition, this invention is not limited by this Example.

  FIG. 1 is an explanatory diagram simply showing the configuration of an electrolyte analyzer according to an embodiment of the present invention. In FIG. 1, the electrolyte analyzer comprises a sample supply means 10, a diluent supply means 20, a standard solution supply means 30, a measurement means 40, and a heat exchanger (heat exchange means) 50. It is.

  The sample supply means 10 includes a sample container 11 and a sample dispensing nozzle 12. The sample container 11 contains a sample such as urine or serum. The sample dispensing nozzle 12 dispenses a certain amount of sample from the sample container 11 and dispenses it to the dilution container 60.

  The diluent supply means 20 includes a diluent container 21 and a diluent separator 22. The diluent container 21 contains a diluent for diluting the sample. The diluted solution dilutes the sample, for example, about 30 times, thereby generating a sample solution.

  The diluent separator 22 is connected to the diluent container 21 via the diluent inlet pipe 23 and is connected to the diluent outlet nozzle 25 via the diluent supply pipe 24. The diluent introduction pipe 23 is a conduit for guiding the diluent from the diluent container 21 to the diluent separator 22. The diluent supply pipe 24 is a conduit for supplying the diluent from the diluent separator 22 to the diluent dispensing nozzle 25. The diluent supply pipe 24 is provided with a diluent supply valve 26 at a predetermined location, that is, a location where the diluent supply pipe 24 communicates with the diluent dispensing nozzle 25. The diluent dispensing nozzle 25 is for dispensing the diluent from the diluent supply pipe 24 to the dilution container 60.

  Although the details will be described later, the diluent separator 22 separates a predetermined amount of the diluent from the diluent container 21 through the diluent introduction pipe 23 and sends it to the diluent supply pipe 24.

  The standard solution supply means 30 includes a standard solution container 31 and a standard solution separator 32. The standard solution container 31 contains a standard solution for use in measuring the sample solution.

  The standard liquid separator 32 is connected to the standard liquid container 31 via a standard liquid introduction pipe 33 and is connected to a standard liquid dispensing nozzle 35 via a standard liquid supply pipe 34. The standard solution introduction pipe 33 is a conduit for guiding the standard solution from the standard solution container 31 to the standard solution separator 32. The standard liquid supply pipe 34 is a pipe line for supplying the standard liquid from the standard liquid separator 32 to the standard liquid dispensing nozzle 35. In the standard liquid supply pipe 34, a standard liquid supply valve 36 is disposed at a predetermined position, that is, a position where the standard liquid supply pipe 34 communicates with the standard liquid dispensing nozzle 35. The standard liquid dispensing nozzle 35 is for dispensing the standard liquid from the standard liquid supply pipe 34 to the dilution container 60.

  As will be described in detail later, the standard liquid separator 32 separates a predetermined amount of standard liquid from the standard liquid container 31 through the standard liquid introduction pipe 33 and sends it to the standard liquid supply pipe 34.

  The measurement means 40 includes a measurement liquid supply pipe 41, an electrode part 42, an electromotive force measurement part 43, and a measurement part 44. One end of the measurement liquid supply pipe 41 is connected to the dilution container 60, and the other end is connected to the waste liquid container 61. The measurement liquid supply pipe 41 is provided with a measurement liquid suction part 45 at the other end side. The measurement liquid suction unit 45 is for sucking the measurement liquid in the dilution container 60, that is, the sample solution or the standard liquid, and sending it to the waste liquid container 61. That is, the measurement liquid supply pipe 41 is a pipe for guiding the measurement liquid (sample solution, standard solution) inside the dilution container 60 from the dilution container 60 to the waste liquid container 61 by the action of the measurement liquid suction part 45. Road.

  The electrode part 42 is disposed at a predetermined position of the measurement liquid supply pipe 41, that is, at a position upstream of the position where the measurement liquid suction part 45 is disposed. The electrode portion 42 includes an ion selective electrode and a comparison electrode (both not shown). The ion selective electrode is an electrode that exhibits a potential in response to specific ions such as sodium ion, potassium ion, and chlorine ion. These ion-selective electrodes and comparative electrodes are for indicating the respective potentials of the measurement liquid (sample solution and standard solution) passing through the location where the electrode portion 42 of the measurement liquid supply pipe 41 is provided. More specifically, the ion-selective electrode and the reference electrode have a reference liquid (hereinafter referred to as REF) that is used for the electrode portion 22 when the measurement solution passes through the electrode portion 42 of the measurement solution supply pipe 41. (Also referred to as a liquid) to indicate the potential of each of the measurement liquids that pass through.

  The electromotive force measurement unit 43 measures the electromotive force of each of the sample solution and the standard solution that passes through the measurement solution supply pipe 41 through the electrode unit 42. More specifically, the electromotive force measurement unit 42 measures the potential difference between the potential indicated by the ion selective electrode and the potential indicated by the comparison electrode with respect to the sample solution passing through the measurement liquid supply pipe 41. The potential difference between the potential indicated by the ion selective electrode and the potential indicated by the comparison electrode is measured with respect to the standard solution passing through the measurement solution supply pipe 41.

  Based on the electromotive force measured by the electromotive force measurement unit 42, the measurement unit 44 determines the concentration of an electrolyte such as sodium ions, potassium ions, and chlorine ions to be measured contained in the sample solution that passes through the measurement liquid supply pipe 41. Measure.

  2 to 3 show an example of a heat exchanger constituting the electrolyte analyzer according to the embodiment of the present invention, FIG. 2 is a plan sectional view, and FIG. 3 is a front sectional view. The heat exchanger 50 will be described below with reference to FIGS. 2 and 3 as well. The heat exchanger 50 is for exchanging heat between the diluent that passes through the diluent supply pipe 24 and the standard solution that passes through the standard liquid supply pipe 34. More specifically, the heat exchanger 50 is as follows. The heat exchanger 50 includes a heat exchanger body 51, a diluent passing part 52, and a standard liquid passing part 53.

  The heat exchanger body 51 is a housing formed of, for example, an aluminum alloy. The diluent passage 52 constitutes the diluent supply pipe 24 and is disposed inside the heat exchanger main body 51. The dilution liquid passage portion 52 is made of, for example, stainless steel and has a shape wound in a coil shape. The standard liquid passage part 53 constitutes a standard liquid supply pipe 34 and is disposed inside the heat exchanger main body 51. The standard liquid passage portion 53 is made of, for example, stainless steel and has a shape wound in a coil shape.

  Further, the dilution liquid passage part 52 and the standard liquid passage part 53 are in a state in which the dilution liquid in the dilution liquid passage part 52 and the standard liquid in the standard liquid passage part 53 are thermally connected. It arrange | positions in the aspect which becomes. That is, a part of the diluent passing part 52 and a part of the standard liquid passing part 53 are arranged in contact with each other.

  Hereinafter, measurement of the electrolyte concentration of the component to be measured contained in the sample solution by the electrolyte analyzer will be described. In the following, for convenience of explanation, both the diluent supply valve 26 and the standard solution supply valve 36 are closed. In the initial state, the diluent is sent to the diluent supply pipe 24 and stays there, and the standard solution is sent to the standard solution supply pipe 34 and stays there.

  In the electrolyte analyzer, the diluent that stays in the diluent supply pipe 24 and the standard solution that stays in the standard liquid supply pipe 34 pass through the diluent passage in the heat exchanger main body 51 (heat exchanger 50). Heat exchange is performed because they are thermally connected to each other through 52 and the standard solution passage portion 53. As a result, the dilution liquid staying in the dilution liquid supply pipe 24 and the standard liquid staying in the standard liquid supply pipe 34 have substantially the same temperature, and the temperature difference between the dilution liquid and the standard liquid is extremely zero. Close to.

  Then, the diluent supply valve 26 is opened, and the diluent remaining in the opened diluent supply pipe 24 is poured into the dilution container 60 through the diluent dispensing nozzle 25.

  Thereafter, the sample accommodated in the sample container 11 is dispensed by a certain amount by the sample dispensing nozzle 12, and the certain amount of the dispensed sample is dispensed into the dilution container 60 from which the diluent has been dispensed. Thereby, in the dilution container 60, the sample is diluted by about 30 times with the diluent, for example, and mixed uniformly by a stirring mechanism (not shown) to generate a sample solution.

  The sample solution generated in the dilution container 60 is aspirated by operating the measurement liquid aspirating unit 45. As a result, the sample solution passes through the measurement liquid supply pipe 41 as the measurement liquid. When the sample solution passes through the electrode portion 42 (ion-selective electrode and comparison electrode) of the measurement liquid supply pipe 41, the electromotive force measurement unit 43 causes the electromotive force of the sample solution through the ion-selective electrode and the comparison electrode. Measure. That is, the electromotive force measurement unit 43 determines the potential difference between the potential indicated by the ion-selective electrode and the potential indicated by the comparison electrode with respect to the sample solution passing through the location where the electrode part 42 of the measurement liquid supply pipe 41 is provided. Measure. Thereafter, the sample solution is guided to the waste liquid container 61 and discarded.

  Next, the standard solution supply valve 36 is opened, and the standard solution staying in the opened standard solution supply pipe 34 is poured out into the dilution container 60 through the standard solution dispensing nozzle 35.

  The standard solution poured into the dilution container 60 is aspirated by operating the measurement liquid aspirating unit 45. As a result, the standard solution passes through the measurement liquid supply pipe 41 as the measurement liquid. When the standard solution passes through the electrode 42 (ion-selective electrode and comparison electrode) of the measurement solution supply pipe 41, the electromotive force measurement unit 43 transmits the electromotive force of the standard solution through the ion-selective electrode and the comparison electrode. Measure. In other words, the electromotive force measurement unit 43 compares the potential difference between the potential indicated by the ion selective electrode and the potential indicated by the comparison electrode with respect to the standard solution passing through the location where the electrode portion 42 of the measurement solution supply pipe 41 is provided. Measure. Thereafter, the standard solution is guided to the waste liquid container 61 and discarded.

  The measuring unit 44 measures the electrolyte concentration of the component to be measured included in the sample solution based on the electromotive force of the sample solution and the electromotive force of the standard solution measured through the electrode unit 42 and the electromotive force measuring unit 43. Thereby, the measurement of the electrolyte concentration of the component to be measured contained in the sample solution by the electrolyte analyzer is completed.

  As described above, according to the electrolyte analyzer according to the embodiment of the present invention, the heat exchanger 50 uses the diluted solution that stays in the diluent supply pipe 24 and the standard solution that stays in the standard solution supply pipe 34. Since they are mutually heat-exchanged, the temperatures of the two are substantially equal, and the temperature difference between the two can be made extremely close to zero. Thereby, a temperature difference between the sample solution measured as the measurement solution by the measuring means 40 and the standard solution is less likely to occur, and the electromotive force measured by the electrode unit 42 and the electromotive force measurement unit 43 is the difference between the sample solution and the standard solution. There is no risk of being affected by temperature differences. Therefore, the electrolyte concentration of the component to be measured contained in the sample solution can be measured accurately and easily.

  According to the above-described electrolyte analyzer, the heat exchanger 50 is simply disposed in the diluent supply pipe 24 and the standard solution supply pipe 34. Therefore, as in the prior art, an apparatus for keeping the temperature of the sample solution and the standard solution constant, In addition, it is not necessary to provide a device or the like for detecting the temperature of the sample solution and the standard solution and correcting the temperature based on the detected temperature, and the entire device is not enlarged. In addition, the cost required for the entire apparatus can be reduced.

  In the above electrolyte analyzer, a dilution solution is supplied to the dilution container 60 to generate a sample solution, and after measuring the electromotive force of the sample solution, the standard solution is supplied to the dilution container 60. Since the electromotive force of the standard solution is measured, that is, the supply of the dilution solution and the supply of the standard solution are performed alternately, the standard solution also serves to clean the dilution container 60, the measurement solution supply pipe 41, and the electrode unit 42. It will be. Therefore, it is not necessary to provide time for cleaning, and the measurement time can be shortened.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to this, and various modifications can be made. For example, a heat transfer medium having a high heat transfer effect may be enclosed in the heat exchanger body of the heat exchanger. Moreover, the dilution liquid passage part and the standard liquid passage part may be in contact with each other over the entire length as well as a part thereof. Thereby, the heat exchange rate between the diluted solution and the standard solution can be sufficiently increased. Furthermore, the whole diluent supply pipe may be used as a diluent passage, and the whole standard solution supply pipe may be used as a standard solution passage. Also by this, the heat exchange rate between the diluted solution and the standard solution can be made sufficiently high, and the diluted solution and the standard solution can easily maintain the temperature after the heat exchange.

  As described above, the electrolyte analyzer according to the present invention is useful for measuring the electrolyte concentration in a sample such as urine or serum.

It is explanatory drawing which showed simply the structure of the electrolyte analyzer which concerns on the Example of this invention. It is plane sectional drawing which showed an example of the heat exchanger which comprises the electrolyte analyzer which concerns on the Example of this invention. It is front sectional drawing which showed an example of the heat exchanger which comprises the electrolyte analyzer which concerns on the Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Sample supply means 11 Sample container 12 Sample dispensing nozzle 20 Diluent supply means 21 Diluent container 22 Diluent separator 23 Diluent introduction pipe 24 Diluent supply pipe 25 Diluent dispensing nozzle 26 Diluent supply valve 30 Standard Liquid supply means 31 Standard liquid container 32 Standard liquid separator 33 Standard liquid introduction pipe 34 Standard liquid supply pipe 35 Standard liquid dispensing nozzle 36 Standard liquid supply valve 40 Measuring means 41 Measurement liquid supply pipe 42 Electrode section 43 Electromotive force measurement section 44 Measuring Unit 45 Measuring Solution Suction Unit 50 Heat Exchanger 51 Heat Exchanger Body 52 Diluent Passing Portion 53 Standard Solution Passing Portion 60 Dilution Container 61 Waste Liquid Container

Claims (2)

A diluent supply means for supplying a diluent for diluting the sample to produce a sample solution to the dilution container;
A standard solution supply means for supplying a standard solution to the dilution container;
In an electrolyte analyzer comprising: a measuring means for measuring an electrolyte concentration of a component to be measured contained in the sample solution by measuring each electromotive force of the sample solution and the standard solution using an ion selective electrode. ,
An electrolyte analyzer comprising heat exchange means for exchanging heat between the diluent supplied by the diluent supply means and the standard solution supplied by the standard solution supply means.   2. The electrolyte analyzer according to claim 1, wherein supply of the diluent by the diluent supply unit and supply of the standard solution by the standard solution supply unit are alternately performed.

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